Last week the Supreme Court struck down a law that allowed the government to deport certain immigrants who have committed serious crimes, calling the law too vague to be properly enforced. This case was decided five to four with Justice Neil M. Gorsuch joining the court’s four more liberal members for the first time. In his concurring opinion, Justice Gorsuch writes: “Vague laws invite arbitrary power.”

The case, Sessions v. Dimaya, was first argued in January 2017 before an eight-member court after Justice Antonin Scalia died. Since the voting deadlocked at four to four, it was re-argued in October after Justice Gorsuch joined the court. The case concerns James Dimaya, a Filipino native and lawful permanent resident, who was convicted of residential burglary. The government wanted to deport him saying that he had committed an “aggravated felony,” and the case before the Supreme Court dealt with the definition of a "crime of violence."

Justice Elena Kagan, writing for the majority, cites the reasoning in a prior case, Johnson v. United States, for why this law was struck down. Justice Kagan references Justice Scalia’s own majority opinion in Johnson, citing the statement that "the prohibition of vagueness in criminal statutes" is "essential" for due process and for "ordinary notions of fair play and the settled rules of law." She notes that lower courts haven't been able to consistently apply the law. In his concurring opinion, Gorsuch writes that “no one should be surprised that the Constitution looks unkindly on any law so vague that reasonable people cannot understand its terms and judges do not know where to begin in applying it.”

Tyler Q. Houlton, a spokesman for the Department of Homeland Security, says the ruling would undercut “efforts to remove aliens convicted of certain violent crimes, including sexual assault, kidnapping and burglary, from the United States.” He adds: “By preventing the federal government from removing known criminal aliens, it allows our nation to be a safe haven for criminals and makes us more vulnerable as a result.” President Trump tweeted that the court’s decision “means that Congress must close loopholes that block the removal of dangerous criminal aliens, including aggravated felons. This is a public safety crisis that can only be fixed by Congress -- House and Senate must quickly pass a legislative fix to ensure violent criminal aliens can be removed from our society.” It should be noted that the court’s decision does not prevent the government deporting individuals convicted of such violent crimes or serious offenses as murder, rape, or drug trafficking.

In response to the Supreme Court’s decision, immigration advocates say it will affect many thousands facing removal from the US. Michael Kagan, professor and director of the Immigration Clinic at the University of Nevada Las Vegas, notes that the decision is "another sign from the court that due process matters when it comes to deportation." E. Joshua Rosenkranz, the lawyer for James Dimaya, says: “This decision is of enormous consequence, striking down a flawed law that applies in a vast range of criminal and immigration cases and which has resulted in many thousands of immigrants being deported for decades in violation of their due process rights.”